H.1. ipcalc and other IP addressing calculators

There are a number of different utilities called ipcalc, almost all of
which perform the same basic task. These are handy calculators for
converting from CIDR to traditional IP notation and determining network
and broadcast addresses.

A short
perl
script, this prints out alll the information you would
want to know about an IP address. It defaults to print colorized
output, and comes with its own CGI (shown running
here).

For those who perform all operations and research through a web
browser, a
DHTML
calculator should do the trick.

You can run this
ipcalc,
which features hexadecimal as well as decimal output, on your PDA.

RedHat has created their own ipcalc utility
which prints out a shell variable assignment command instead of
simply the requested piece of information. In the startup
scripts, RedHat evals this variable assignement into existence.
Despite this shortcoming, it is a useful tool and is documented
in its manpage (part of the initscripts RPM).

Doubtless, there are a large number of other IP calculators available
to ease the job of the network administrator. The above tools are
meant as a brief summary of some of the offerings.